Reznor Gas Conversion Kit Installation Guide for Unit Heaters

Quick guide from the manual

This document provides instructions for converting Reznor unit heaters between natural gas and propane. It covers kit selection, component installation, and pressure adjustment. Warning: Gas conversion must be performed by a qualified service person. Improper installation can result in fire, explosion, injury, or death.

Kit selection

Before beginning, identify your heater model and unit size. Refer to Table 1 (Natural Gas to Propane) or Table 2 (Propane to Natural Gas) to select the correct kit components. Ensure you have the correct spring kit, burner orifices, and air restrictor plate for your specific unit size and gas valve type.

Installation steps

Follow these steps to perform the conversion:

1. Shut down: Turn off the gas supply at the shutoff valve and disconnect electrical power. Open the control access panel.
2. Regulator spring kit: Install the regulator spring kit corresponding to your gas valve. Do not interchange kits. Follow the gas valve manufacturer's instructions included with the spring kit.
3. Air restrictor plate: Install or remove the air restrictor plate based on the fuel type and unit size. For propane conversion on specific sizes, the plate must be installed; for natural gas, it must be removed. Use pliers to bend or unbend the tabs on the venturi tube to secure or release the plate.
4. Burner orifice: Replace the burner orifice with the size specified in Table 3. Do not attempt to drill the orifice; use only factory-supplied parts.
5. High elevation: If the heater is operated at an elevation above 6,000 feet (1,830 meters), a high-elevation pressure switch must be installed.

Manifold pressure adjustment

After installing the conversion kit, you must adjust the manifold pressure:

• Connect a manometer to the 1/8-inch output pressure tap on the gas valve.
• Turn the gas valve to ON and operate the heater.
• Adjust the regulator screw (IN to increase, OUT to decrease) until the pressure matches the values in Table 4 for your elevation.
• Caution: Do not bottom out the regulator screw, as this can cause unregulated pressure and heat exchanger failure.
• Perform a leak test on all connections using a commercial leak-detecting fluid or soap solution.

Safety and maintenance

Always verify the input rate on the heater rating plate after conversion. If the unit is adjusted for high-elevation operation, the input rate will be affected. Ensure the high-elevation adjustment label is filled out and affixed to the heater access panel if required.